In the first post in this series on Aquinas’s Fourth Way, we compared his Argument from Degrees of Perfection to modern moral arguments, showing that the latter are based on the assumption of a “fact/value” distinction in nature, which is completely antithetical to Aquinas’s own view. In the second, we explored the classical understanding of “the good” as being based objectively in the very structure of reality itself; and then introduced the doctrine of “the Transcendentals”, which argues that there are certain transcending properties of all existing things that are over and above all categories, classes, aspects, and individuals. These are being, goodness, truth, and unity. In this post, we will present the argument itself.
As was quoted at the end of the introduction, here is the argument in Aquinas’s own words:
“The fourth way is taken from the gradation to be found in things. Among beings there are some more and some less good, true, noble, and the like. But more and less are predicated of different things, according as they resemble in their different ways something which is the maximum, as a thing is said to be hotter according as it more nearly resembles that which is hottest; so that there is something which is truest, something best, something noblest and, consequently, something which is uttermost being; for those things that are greatest in truth are greatest in being, as it is written in Metaph. ii. Now the maximum in any genus is the cause of all in that genus; as fire, which is the maximum heat, is the cause of all hot things. Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God” .
As shall become clear, a defense of the argument will require a bit of extrapolation.
The Fourth Way is widely regarded “to be among the most Platonic elements of Aquinas’s thought” , and it is for that reason, notes philosopher Ed Feser, that it is also considered “the most difficult . . . to accept, or even to understand”, and is judged by some as “strange” and “bizarre” . Hence in order to understand the argument more fully, we will here present the common “Platonic” interpretation, see why it is mistaken, and in so doing answer a number of frequent objections.
For Plato, in order to make sense of the simultaneous unity and multiplicity, and change and stability, of things, and likewise in order to make sense of how we know things, we must appeal to something like the forms, as his own famous Theory of Forms does. According to this, there is a “third realm”, apart from the material and mental realms, in which there exist pure, independently real, ideal, immaterial, eternal, unchanging and universal forms, or “essences” of things. This is not true just of substances, such as a triangle or a horse or a tree; it is true also of “accidents” such as whiteness, tallness, strength, etc. Although Aristotle would later regard this as sheer incoherence, Plato would indeed maintain that “whiteness” exists as a pure form completely on its own, separate from any other object, even though in our experience whiteness can only ever be a property of things. Plato held that our finite, material universe is merely a shadow or “copy” of the true world of forms, which is more purely real.
As Feser writes, Plato thought that “the ordinary objects of our experience can only be understood in term of their ‘resemblance’ to or ‘participation’ in ideal archetypes of which they are imperfect copies” . Consider human beings. We all, in a sense, are the same; we all “share in” humanity, the common human essence. But at the same time, we’re all different, independently existing beings with unique properties. One human will be male, another female. One will be tall, another short. One will have black hair, another blonde, another brown, etc. These accidental features, then, cannot be intrinsic to the essence of humanity itself; for if it were, all humans would have those exact same features. Furthermore, not all humans perfectly instantiate the full essence of humanity. For its seems that the essence of humanity (as rational animals) includes things like “sense perception”, but some humans, such as the blind or deaf, either by injury or genetic defect, lack these essential features. And even if all actual human beings suddenly ceased to exist, the essence of humanity would seem to still exist, since we can still understand it as an idea/concept, and define it, without it actually existing (as we can define a unicorn or dragon). So the essence of humanity cannot be a material being. But nor, argues Plato, can it be mental being, existing only in human minds, since it is objective, discovered by us rather than invented (consider mathematical truths to see this). So it must exist on its own, as a special kind of being beyond all physical and mental reality; and this is the realm of the forms . The objects of our experience thus “participate” in the eternal forms which they resemble/instantiate. According to the cosmology of Plato’s Timaeus, our world exists because a divine craftsman took imitations of the eternal forms and instantiated them in a pre-existing, primordial, formless chaotic matter.
For an illustration of how this plays out, consider the case of “beauty”. In fact, this example in many ways seems quite similiar to the Fourth Way, and thus gives an excellent indication of how some interpret the Fourth Way in light of a Platonic metaphysics. In Plato’s Symposium, Socrates argues that love is a desire for beauty/goodness: “In a word, then, love is wanting to possess the good forever” , and by this he means the ultimate “form of the good”, which is actually the highest and purest of all forms, the very ground of their being (see his allegory of the cave in the Republic for further explanation of this). But, he insists, we only come to know/possess the good by recognizing its hierarchical inherence in material things. Thus we first will come to know and desire the beauty in physical bodies of people; then we will comes to know and desire the higher beauty of their soul (or personality); then we will come to know and desire the even higher beauty of knowledge of ideas/forms themselves, which will lead us finally to know and desire the highest good/beauty, that of the form of good/beauty itself. Every instantiation of this ultimate form is lower in quality and perfection; it is an “imperfect” instantation of the pure form, not fully capturing its total essence and reality.
Now it becomes immediatley clear in what respects the Fourth Way seems platonic. Aquinas notes that there is a “gradation”, or succession of degrees, of qualities in beings, very much like the “hierarchy” of beauty just discussed. But, says Aquinas, “more and less are predicated of different things, according as they resemble in their different ways something which is the maximum” and “the maximum in any genus is the cause of all in that genus”. Does this “maximum” not sound suspiciously like the maximum found in the ideal form of things in Plato’s framework? And, just as Plato says the objects of our experience “resemble” or “participate in” their ideal forms, so here Aquinas says that these gradations of qualities “resemble” their maximum, which is indeed their “cause”. Feser writes:
“Unlike the rest of the Five Ways, the Fourth Way seems (at least in its first stage) to be concerned with explaining the world in terms of formal rather than efficient causality . . . The thrust of the argument might therefore seem to be that we can only make sense of the more or less good, true, and noble things of our experience by reference to something like a divine Platonic archetype of goodness, truth, and nobility . . . Furthermore, the apparent emphasis on formal rather than efficient causality might seem to explain why Aquinas thinks that the maximum in any genus is the ’cause’ of everything in that genus” .
On this platonic interpretation, the argument goes something like this: there are certain qualities of things that inhere in their objects to different degrees. For example, different trees might be better or worse, depending on how well they resemble the ideal form of treeness. And different elephants might likewise be better or worse for the same reason. But then, in each type of being, there is a range of possible gradation of goodness which can inhere therein. How can we make sense of the fact that trees can be more or less good, and elephants can be more or less good, and triangles and people and etc., that all these various, different types of beings can similarly “share in” goodness, unless there is some maximum “goodness” over and above all these different types of beings, which they resemble or particiapte in? In other words, a tree is good insofar as it resembles the form of a tree; but that “goodness” itself which it has is only good in itself insofar as it resemles some ultimate form of goodness.
This is the platonic interpretation, and it is this that has rightly been criticized as mistaken. Why reject it? Feser gives the chief and simple reason:
“There is one glaring problem with a Platonic interpretation of the Fourth Way, which is that Aquinas was not a Platonist, but rather an Aristotelian” .
Which, of course, should be fairly obvious, and yet is still missed. Aquinas thinks that the forms of things exist in them, or else in a mind that grasps them abstractly; not in some independently existing “third realm”of pure, ideal forms which physical objects “copy” or “resemble” or “participate in”.
So how ought the argument actually, correctly be understood?
First, an admission must be made. Aquinas, in his own presentation of the argument, makes a reference which to modern readers seems just laugahbly false. Unfortunatley, many people, upon realizing this, then immediately jump to the conclusion that the entire argument must therefore be incorrect, maybe even “laughably” so. The reference in question is to “fire” as the “maximum heat” and the cause of all heat. Medieval thinkers archaicly thought that fire is the source of all heat , and thus the example of fire is a natural one for Aquinas to use to explain the principle he is laying down. But the example of fire has absolutely no bearing whatsoever on the actual success or failure of the argument itself, at all. None. Period.
This should be evident just by a surface reading of the argument; but some still seem to think otherwise. The reason, however, why it is indisputably the case that the example of fire/heat has no relevance whatsoever to the argument itself is fairly simple: the argument is an attempt to establish the existence of God, who Aquinas holds in principle to be non-physical and incoporeal–so it is just nonsensical to think that Aquinas would then argue that “heat” or “fire” are attributes of the Divine Nature. Unfortunatley, many modern readers seem incapable of exercising the principle of charity in trying to properly interpret the actual point of the argument as a whole, and thence write Aquinas off as “hopelessly pre-scientific”. (Note that the reason the medievals held this scientific view about heat and fire is not as ridiculous as it may sound. For consider what happens when we take some object and increase its heat. Eventually, the more heat we apply to it, it will reach some “combustion point” where it catches fire. Thus it’s somewhat natural to think that fire is the “maximum” of heat).
Rather, the conclusion of the argument should make very clear what Aquinas is getting at: “Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection”. So his argument is not meant to concern heat or just any quality of things that could possibly admit to degrees; it is concerning specifically “being, goodness, and every other perfection”. Or, in other words, the Transcendentals, which we’ve already discussed. (There is actually an argument that could possibly be made from other qualities, but that is distinct from the Fourth Way and thus will not be considered here).
To begin to delve into the argument itself, take a class of some type of beings, such as, say humans. It is certainly true that among humans “there are some more and some less good”. If goodness, as we’ve seen, consists of fulfilling the perfective ends of something, and if in humans this includes moral goodness, then it just obvious that there are some humans with more moral goodness, and some with less (since for Aristotle and Aquinas being virtuous is a “state” of the soul such that it is possible to say that some person is a virtuous person or not a virtuous person, and a virtuous person will more wholly fulfill the ends of human nature, since human nature is to be a rational animal and virtue is in accord with reason; hence a virtuous person is a “more good” human than a non-virtuous person). Thus in humans there is an obvious range of degrees of goodness. But this range of gradation points to an evident maximum. For if one human is “more good” than another by way of more perfectly fulfilling the ends of human nature, than it is the case that some ideal “best human” would completely and wholly perfectly fullfill all ends of human nature (even if such an ideal “maximum human” would never actually exist). Thus within this one class of existing things, there is a hierarchy of beings reaching and pointing to some possible maximum being.
But there is not just one class of existing things, there are many various different classes of existing things. Humans and polar bears and atoms and stars and circles and blades of grass, etc., etc., etc., etc. And within each class that admits to gradation of goodness, being, and the like, there would theoretically be a similar type of hierarchy pointing to some possible maximum thereof. But this presents us with a hierarchy emerging from the classes of things themselves–a hierarchy of being, reaching from the lowest, most basic, fundamental particles of matter in physical reality, up through the atoms, molecules, complex objects, leaping up from inanimate beings to single living cells, then complex living organisms, from plants, to animals, and finally, the summit of physical reality, human beings who are rational animals. Each “level” on this hierachy has more being, and therefore more goodness, since each level has a higher degree of perfection. This should not really be a controversial claim, since even reductive materialists admit that the “higher” beings, even though they essentially are just organized collections of the lower beings, are still more complex and have higher functions. On St. Thomas’s view, these beings are not just higher insofar as they have increased complexity in terms of interaction of lower beings; rather, they also have higher forms, with more intrinsic being and actuality. For the functions or “powers” that a certain being has flow from its form/nature, which is its actuality. A simple life form may have the actuality to be capable of growth, reproduction, etc., but higher life forms will have these same powers, as well as additional ones, such as locomotion, sense-perception, and, finally, rationality. Note here that “higher” does not just mean “quantitatively more”, for if that were the case, then massive stars or black holes would be the highest level of being capable in our universe, since these objects contain astronimcally more mass and energy then miniscule human beings do. A thing is “higher” in degree of being and goodness in terms of its intrinsic actualities and powers; its qualitative functions. Thus a star, which is certainly maginificent and impressive, is essentially an ongoing process of intense nuclear fusion, which is, at base, merely a form of chemical reaction. This is thus the highest qualitative power of a star. But even the most basic, simplest of living organisms exceeds this, since these likewise have the chemical powers, but in addition also have the powers unique to living things, as listed above. Hence living things, in terms of qualitative power/actually, exceed non-living things. And in the order of living things, plants exceed simple life forms, animals exceed plants, and humans exceed all. Furthermore, if anything like angels exist in any form, which are purely immaterial beings, they would exceed even humans.
So Aquinas writes:
“A thing is perfect in proportion to its state of actuality, because we call that perfect which lacks nothing of the mode of its perfection . . . This word ‘perfect’ signifies whatever is not wanting in actuality . . . Existence is the most perfect of all things, for it is compared to all things as that by which they are made actual; for nothing has actuality except so far as it exists. Hence existence is that which actuates all things” [9.
If a bird, by virtue of being what it is, has the potency or potential to fly, but never actualizes this potency, never actually flies, then it is imperfect; it is “lacking” something “of the mode of its perfection”, since to fly is a perfection of the essence of being a bird. But when it does actually fly, it actualizes this perfection. But obviously, a thing can only share a perfection insofar as it actually exists; hence “existence is the most perfect of all things”, since it is by existing, and existing fully, that natures are perfected.
So amongst all existing things in reality we acknowledge that there is a definite hierarchy of beings in terms of their intrinsic level of actuality. Just as in a single class of things, wherein certain individuals might be superior to others in terms of more perfectly fulfilling the ends of their essence/nature in a way so as to constitute a hierarchy within the class, similarly among all classes of all beings, the classes themselves form an ordered hierarchy, in terms of the degree to which they more fully participate in higher qualitative perfections. But, then, we must also recognize that just as the hierarchy within each individual classes pointed to some possible “maximum” of goodnes, being, and perfection within that class–as fire is the maximum of heat, and the “ideal” human, who wholly fulfills all the perfective ends of the essence of a human being, is the maximum human–so also the hiearchy of all classes of all beings points to some “maximum” of all being, all goodness, all actuality, all perfection.
Now, obviously, just as this “ideal” human as the possible maximum of humanity unfortunatley does not actually exist (so far as we can tell), the mere fact that a hierarchy of gradation of beings “points to” some maximum of all being, goodness, actuality, and perfection does not tell us whether such a Being actually exists in reality. In some cases, the maximum of a class of things might actually exist. But in many cases, it certainly does not. All we have done here is show that the hierarchy of gradation of perfections in beings does exist, and that this hierarchy does really point to some possible Being of Maximum Perfection. But the task is still left to us to actually determine whether or not this Being exists. This is the task we shall undertake in the fourth and final post in this series.
. Aquinas, Thomas. Summa Theologica. 1265-1274. Trans. Fathers of the English Dominican Province. Coyote Canyon Press, 2010. ebook. I, Q. 2, Art. 3.
. Feser, Edward. Aquinas. London: Oneworld Publications, 2009. Print, 100.
. The previous summary of argument is taken from the above cited work. Feser uses “triangles” as his example, I have used humanity, but have followed almost directly the same outline, as I think it best captures Plato’s own understanding.
. Plato. “Symposium,” in Plato: Complete Works. Edited and translated by John M. Cooper. Indianapolis: Hackett, 1997. 489.
. Feser. Aquinas. 102-103.
. Ibid. 103.
. Ibid. 104.
. Aquinas, Thomas. Summa Theologica. 1265-1274. Trans. Fathers of the English Dominican Province. Coyote Canyon Press, 2010. ebook. I, Q. 4, Art. 1.